The Chemical Safety Board has called for the oil giant to appoint a new safety director along with a series of recommendations to improve its safety performance.

The watchdog concluded that “organisational and safety deficiencies at all levels of the BP corporation” caused an explosion at BP’s Texas City refinery near Houston in March 2005, killing 15 people and injuring 180.

The CSB found that the accident happened when a distillation tower was overfilled with hydrocarbons and released highly flammable material into the atmosphere. The report concluded that the incident was caused by safety failings that went beyond specific issues at the site that day and were symptomatic of a wider “dysfunctional safety culture”.

“Many of the safety issues that led to the March 2005 accident were recurring safety problems that had been previously identified in internal audits, reports and investigations,” said supervisory investigator Don Holmstrom.

Three serious incidents at the BP refinery in Grangemouth, Scotland, in 2000 were cited as examples of this poor culture by the CSB. It found that cost targets played a role in these incidents, and that the lessons from them had not been learnt.

BP said in a statement: “Notwithstanding the company’s strong disagreement with some of the content of the CSB report, particularly many of the findings and conclusions, BP will give full and careful considerations to CSB’s recommendations.”